Good morning, @CoreyParchem ...
You can go to your "Courses" >> "All Courses" screen within Canvas to "favorite" any courses you want to see displayed on your Dashboard by marking them with a yellow star. If you do not want them displayed on your Dashboard, then click the yellow star to remove it. Here is a Guide for you with more details:
How do I customize my Courses list as a student?
Also, if you are seeing courses on your "All Courses" list that you don't want to see any more, you'll have to talk with people at your school about this...such as their Online Learning / eLearning / Distance Education department. They may have policies in place where past courses can or cannot be removed.
Sing out if you have any other questions about this...thanks!